Llyn Tegid: Lake Bala – Tegid derives from the prince featured in the “Legend of Bala Lake.” Another possible derivation from “Tacitus,” a Roman general.

Llanuwchllyn: Church above the lake

Llangower or Llangywair: The church of Saint Cywair

Llanycil: The church in a sheltered enclave or retreat

Llandderfel: The church of Saint Derfel

Llandrillo: The church of Saint Trillo

Llanfor: (Llan + mawr) The principal church of Penllyn at one time

Llangwm: The church in the valley

Cefnddwysarn: The hillside of the two roads. “Sarn” from Latin “strata” (road)

Sarnau: plural form of “sarn” – the Roman roads

Penllyn: The upper (Dee) valley area around the lake

Rhosygwaliau: Rhos (heath) + gwaliau (walls or enclosures)

What exactly is a Llan?
Over 430 places in Wales start with 'Llan'. A 'Llan' was a piece of land, usually circular, enclosed by a wooden fence within which would be a church and, occasionally a Christian community. Each 'Llan' was established around the 6th century by various Celtic saints after whom many (but not all) of the sites were named.